Grinding-mill.



J. A. WELTON.

GRINDING 1111111,. APPLICATION FILED DEG. 2, 1912 1,087,415. Patented Feb. 17,1914.

2 SHEETS-SHEET 1.

A Home J. A. WELTON.

GRINDING MILL.

APPLICATION FILED DBO. 2, 1912.

1,087,415. Patented Feb. 17, 1914.

2 SHEETS-SHEET 2.

INVENTOR 30170 flfi kbrd, u I waltw M A ltarney JOHN A. WELTON, OF CANAL DOVER, OHIO.

GRINDING-MILL.

Specification of Letters Patent.

Patented Feb. 17, 1914.

Application filed December 2, 1912. Serial No. 734,593.

To all whom it may concern Be it known that I, JOHN A; WELToN, a citizen of the United States, residing at Canal Dover, in the county of Tuscarawas and State of Ohio, have invented certain new and useful Improvements in Grinding- Mills, of which the following is a speoification.

This invention relates to certain new and useful improvements in machines for grinding coal, ore, cement, and like material and it consists of the parts, and the constructions, arrangements and combinations of parts which I will hereinafter describe and claim.

In the accompanying drawings forming part of this specification and in whlch similar reference characters indicate like parts in the several views; Figure l is a vertical, longitudinal sectional view of a coal crusher embodying the salient features of my invention; Fig. 2 is a cross sectional view on the line XX of Fig. 1. Fig. 3 is a sectional view on the line YY of Fig; 1.

Fig. 4 represents a feeding mechanism of modified form. Fig. 5 is a perspective view of a crushing roll showing the spirally arranged wings or vanes. Fig. 6 is a detail showing the grooved or ribbed surfaces of one of the muller wheels. Fig. 7 is a cross section of the grinding cylinder showing the keys or ways for locking the lining against rotation. Fig. 8 illustrates a modified form of lining. Fig. 9 is a cross-sectional view of lining, S, showing a tongue-and-groove connection between the parts thereof.

In carrying out my invention I construct a suitable frame or casing, A, in the upper portion of which is mounted or provided a hopper or like recelver for the coal or material to be crushed or ground, said casing being fashioned with a receiving chamber, A, into which the material is delivered from the hopper. The chamber is prefer: ably constructed with a curved bottom, and in said chamber is mounted to operate a roll or rolls, B, having wings or blades, 2, and mounted upon a shaft, 0, journaled in suitable bearings ab in the sides of the,

main frame. 7

In order that the greater portion of the weight of the coal may be supported out of contact with the crushing and feeding rolls v in the hopper and the weight removed from the gates, which form the bottom of V the chamber, A, I place over the said crushing and feeding rolls any suitable form of shield, A upon which the weight of the coal is largely carried. This enables me to operate the gates with less power than would otherwise occur.

The bottom of the chamber, A, is formed in part atleast by suitable gates or plates,

1 which enter the frame from opposite sides and whose inner edges are adapted to approach and recede from each other to regulate the feed of the material from said chamber into a second chamber, E, constructed in the frame immediately below the first-named chamber. The gates or plates, D, control: the communication between the two chambers, and each of these gates is slidably mounted transversely in the sides of the frame and is connected with means for opening and closing the gates in unlson to increase or decrease the distance between the meeting edges of the gates and, therefore, the amount of material permit ted to flow from one chamber to the other. By this means the material may be retained in the first chamber until it is somewhat reduced and may then be fed to the second chamber where it isfurther reduced by a suitable crushing roll or rolls, F, mounted therein upon a shaft, Gr, journaled ho-rizon mechanism may be varied in its character,

the means which I prefer to use for the purpose are herein shown as comprising a screw shaft, H, having quick-threads operating in a nut, I, fixed in the side of the main frame, the inner end of the screw, connecting by a swivel or other joint or head, J, with a socket formed in the outer edge of the gate whereby when the screw is rotated the gate will be caused to move in or out in its guide on the frame to thereby decrease or increase the opening between the two chambers, A and E.

The outer end of the screw shaft, H, is connected to a lever, K, the outer end of which may be in the form of a crank, which in turn is pivotally connected to a link, L, whose lower end is pivotally connected to the outer end of a lever, M, substantially horizontally disposed and having its inner end suit-ably mounted on a shaft, N, which extends horizontally centrally beneath the main frame of the machine, the construction being such that when the shaft is rocked the lever, M, is actuated and through the link, L, and lever, K, the screw is rotated in one of two directions to cause the gate attached to the inner end thereof to be moved either in or out according to the direction of rotation of the screw shaft.

Each of the controlling gates is of the construction herein specified and each is connected to a similar mechanism, one at each side of the main frame or casing and both connected to the aforesaid horizontal shaft whereby the gates operate in unison towardand from each other to regulate the size of the opening between the two crushing chambers hereinbefore mentioned.

From the foregoing explanation it will appear that each of the gates which constitute the bottom of the hopper chamber, may have the form shown in Fig. 2, that is, each gate will be curved for the greater portion of its length to constitute a curved bot tom for the chamber, the inner edge of the gates being designed to substantially meet, in one instance, and to recede from each other, in another instance, to thereby con trol the diameter of the space between the gates and which space forms a discharge through which the coal or ore is permitted, under working conditions, to pass from the hopper into the lower or grinding chamber, E, in which operates the grinding roll, or rolls, F, which may be of any well known and suitable character, the essential purpose of which is to reduce any lumps of material which may pass the gates into the chamber, whereby this material is crushed, and placed in such condition as to be operatively fed to the subsequent grinding action of a muller which I will now describe.

One side of the main frame or casing is provided with outlets E, E which communicate with the lower grinding chamber, E, and fitted to this side of the chamber or casing is a cylindrical extension, 0, which forms a housing or casing for a grinding muller, the outer end of this cylindrical extension being open and communicating with the interior of a fan case, Q, within which operates a revoluble fan, R, of any well known and approved construction, mounted on the horizontal shaft, N, and adapted to discharge the ground material entering the fan case, under more or less pressure. The fan case may have an air inlet Q, in its side, if desired.

As in my former Patents No. 993,928, dated May 80, 1911; 993,929, dated May 30, 1911; and 1,022,805, dated April 9, 1912, the cylindrical fan case may connect with a conduit or connection leading to the in terior of a furnace, whereby the material ground by the present machine may be delivered directly and with some force into the furnace in the form of fine fuel. However, I do not limit the present invention to a furnace-feeding means, as it is quite evident that the material ground in the cylinder, 0, may be discharged and utilized in any desired manner.

The interior of the cylinder, 0, is formed, near one end, with an annular flange, 9, and between this flange and the opposite end of the cylinder and closely fitting the same, is a bushing or lining, S, having its interior fashioned with a step-like formation; that is to say, the inner surface of the cylinder is formed with a series of annular ring-like portions which taper in the direction of the length of the lining, each ringlike portion having its larger diameter pre sented toward the smaller diameter of a preceding ring-section and the larger diameter of the ring-section next the receiving end of the cylinder being presented thereto. By reference to Fig. 1 it will be seen that each of the mullers has its smaller end disposed proximate the larger end of a succeeding muller and the smaller end of one muller is of less diameter than the larger end of the succeeding muller. This arrange ment enables the material ground between the periphery of the muller and the corresponding surface of the lining to pass from therebetween directly into the interior of the next succeeding muller, and as these mullers have open-centers, it is apparent that each muller will discharge the material ground by it directly into the common passageway formed by the open centers of the mullers, where the material may be picked up by the air blast which is induced through these open-centers by the fan, hereinafter described. This arrangement forms a series of shoulders, T, between the adjacent ends of the ring-sections and also provides a series of upwardly inclined grinding surfaces over which the material entering the cylinder and the interior of the lining, will be progressively advanced and ground as it passes thereover to the next succeeding ring-section, this operation continuing during the entire progress of the material through the lining to the discharge end thereof.

Operating in the lining and fixedly mounted upon the horizontal shaft, G, is a series of muller wheels, U, having hub portions and connecting webs and having peripheries V, inclined to substantially conform to the inclination of the co acting ringlike grinding surfaces formed on the interior of the lining, each of the muller wheels operating in conjunction with one of the ringlike surfaces, and effecting a grinding of the material as it passes upwardly and outwardly between the inclined grinding surfaces of the muller and lining.

In order that the degree of fineness of the material ground may be regulated, as desired, I may provide adjusting screws, W, operating in the flange, g, of the cylinder and bearing against the end of the lining whereby the lining may be adjusted lengthwise, relatively to the mullers to increase or decrease the space between the opposed grinding surfaces and thereby determine the degree of fineness to which the material shall be reduced.

On the outer end of the shaft, G, and on the end of the shaft of the upper roll, C, are mounted sprocket wheels, X and X, around which pass a suitable sprocket chain, Y, the tension of which may be maintained by some appropriate form of belt tightener, Z, which in the present instance is shown as being spring-actuated. This belt tightener and the sprocket wheels and chain before mentioned are preferably inclosed in a housing or casing, B, as shown in Fig. 3, whereby these parts are protected from excessive wear by reason of the presence of dust and other foreign matter. Also, if desired, one side of the main frame or casing may be provided with an opening, h, which is controlled by a gate or damper, Z, connected by a link, m, to an arm, n, on the shaft, whereby the gate may be opened when desired for the admission of air to mix the fuel under treatment. This is desirable where the machine is used in connection with a furnace for feeding air and fuel to the latter.

In operation, the coal or other material is fed into the hopper in any suitable manner, and part of the weight thereof is sustained by the curved plate or shield, r which lies immediately over the feed roll, B, and which roll is preferably provided with wings or vanes, 2, to assist in feeding the material through the hopper, and for keeping the material in a loose state in said hopper. The lower roll or the roll in the lower chamber, E, is also provided with wings or vanes, 3, and in its rotation, the wings tend tothrow the material up into the top of the chamber by centrifugal force and this action is maintained until the material is reduced to such a degree of fineness that the suction created by the fan, R, at the outer end of the cylinder, 0, overcomes the centrifugal force exerted on the material by the lower roll and the said material is thereby drawn into the cylinder and through the interior of the lining and as it passes through the latter over the inclined grinding surfaces, it is acted upon successively by the muller wheels until it finally issues from the cylinder into the fan-casc, and is discharged therefrom as a finely divided product, such as may be used in furnaces constructed to burn finefuel.

If desired, the faces of the muller wheels advanced by the pressure due to the cen trifugal force of the mullers, and the arrangement of the ribs; the coal is caused to feed from one end of the muller toward the other end and the centrifugal action of the muller, plus the ribs on the outer surface of said muller, will result in the coal being given a continuous movement while passing through the space between the exterior of a muller and the co-acting surface of the lining.

The lining may also be constructed of one cylindrical piece, or it may be made of segmental sections with tongue and groove connection, 4, therebetween, and the surfaces of the muller and interior of the cylinder may also be provided with a tongue and groove connection, 5, which will permit the lining to be adjusted lengthwise and yet will pre vent its rotation relatively to the cylinder. It is also apparent that instead of making the lining with the step-like portions herein referred to, each section of the same may be independent of the others thus forming a lining made of a series of separate rings, S, having cylindrical exteriors and tapering interiors, without departing from the spirit of my invention. In either instance, the material is caused to pass over the inclined or slanting surfaces of the interior of the lining, which clears the cylinder of the accumulating material and increases the capacity of the machine and also makes the machine work easier.

In the bottom of the lower chamber, E, is formed a recess, 10, in which operates a steel strip, 11, which acts as a wearing plate, this strip being loosely mounted and being loosely connected with a bolt, 12, which passes through the bottom of the easing or frame .and is secured on the outside by a nut, 13. This strip is compressed by a spring, 16, which surrounds the bolt and bears under the plate, thereby permitting the plate to yield whenever a hard substance passes between it and the roll.

It will be readily understood that any desired means may be employed for feeding material into the crushing cylinder. In Fig. 1 I show one type of feeding means and in Fig. 4 I show a different type, wherein the material is dumped into a tubular damper, 30, which is supported above the center of a horizontally rotatable disk, 31,

having a raised or conical center for direct-v a ing the material toward the edge of the disk, the disk being provided with a toothed surface, 32, to be engaged by the beveled pinion, 33, mounted on a shaft, 34, jou rnaled in the casing and operated by any well known means. When this pinion is operated the disk is in turn rotated and the material is carried by centrifugal action over the upper face of the disk and discharged over the edge thereof, it being understood that the disk will be appropriately mounted for rotation. The damper may be adjusted relatively to the disk by means of a lever, 35, suitably connected to the damper and universally joined to the frame in some appropriate manner.

in my prior patents before referred to I have shown other types of feeding means and accordingly I wish it understood that so far as the present invention is concerned, the novel features may be used in connection with any means which will appropriately feed the material into the crushing cylinder under a regulable control. It will be further understood that the wings of the crushing roll may be inclined or spirally formed as shown in Fig. 5, so as to facilitate the feeding of the material out of the crushing chamber into the grinding cylinder to be acted upon by the mullers; and that the faces of the muller wheels and the corresponding faces of the lining in be spirally or otherwise roughened as shown in Fig. 6 to promote the grinding of the material passing between these faces.

hen the lining is made of separate annular portions or rings it may be desirable to provide the adjacent rings with the tongue-ai idgroove connection, 36, as shown in Fig. 8, with a spring, 37, backing against one of the members and adapted to hold the rings back together against the action of the adjusting screw.

I may also make the grinding cylinder and fan case in sections, and when this is done Iinterpose between the meeting edges of the sections flat bars, 38, as shown in Fig. 7, which are designed to act as keys for the lining and which act as guides along which these parts may be moved, these strips also serving for locking the lining to the cylinder and thereby preventing the rotation of said linin In Fig. l I show an opening, E above and an opening E below the shaft, C, these openings forming outlets from the crushing chamber into the grinding cylinder, one of these openings, E, 1')e1.'mitting the material thrown up by the centrifugal action of the crushing roll to be sucked forward into the grinding cylinder, or chamber in which the imillers operate; the lower opening, E is employed for the purpose of allowing the crushed material to be fed forward into the grinding cylinder by the spiral wings on the crushing roll.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is 1. In a grinding mill, the combination of a casing and revoluble mullers arranged therein in succession, said mullers having substantially truncated form, and said casing having corresponding grinding surfaces, each of said mullers having its smaller end disposed proximate the larger end of a succeeding muller, and the smaller end of one muller being of less diameter than the larger end of the succeeding muller, and each of said mullers having an opening through it whereby the openings through the several mullers form a passage for the ground material, and means for inducing a draft through said casing and passage.

2. A grinding mill having a casing with an inlet at one end and an outlet at the opposite end, and mullers revoluble in the casing and each provided with an opening between its circumference and center, said casing having a plurality of interior grinding surfaces of substantially truncated form and arranged in succeeding order, and said mullers being of substantially truncated form with the smaller end of one muller disposed proximate the larger end of an adjacent muller and of less diameter than the latter, and means for inducing a draft to traverse said casing from inlet to outlet.

In a grinding mill, the combination with a casing having an inlet and outlet and having an interior series of grinding surfaces arranged in succession, and a series of revoluble mullers of substantially truncated form each having a passageway through it between the circumference and center, each of said mullers having its smaller end of less diameter than the larger end of a succeeding muller, and means for inducing an air current through said casing and mullers whereby said current serves as a vehicle for conveying the ground material from the several mullers to the common outlet of said casing.

4. In a grinding mill, the combination with a casing having a crushing chamber and a crushing member operable therein, said casing having an air inlet to the crushing chamber and a discharge opening lead ing from said chamber, of a side extension of the casing having one end fixed thereto and connectil'ig with said opening whereby it directly receives material from the crushing chamber, muller rings operable in said extension having peripheral grinding surfaces inclined to the axis of said rings, said muller rings having open centers through which. the grinding material is caused to pass, a rotatable shaft upon which the muller rings are mounted and grinding surfaces within the extension opposing the muller rings and inclined to substantially correspond to the inclination of the grinding surface of said rings, the space between a grinding surface and the face of an oppos ing muller connecting with the open center of a succeeding mullerring.

5. In a grinding mill, the combination with a frame or casing having a crushing chamber and a crushing member operable therein, said. frame or casing having an air inlet and a side outlet from the crushing chamber, a cylinder having one end conmiunicating with said opening, whereby the material is received into the cylinder from said chamber, a lining for the cylinder composed of a longitudinal series of annular portions each having an internal grinding surface inclined to the axis of the cylinder, a series of muller wheels within the lining, each of said wheels having a peripheral grinding surface inclined to the axis of the wheel and substantially corresponding to the inclina tion of a companion annular portion, each of said rings having its smaller end disposed proximate the larger end of a succeeding ring, and the smaller end of one ring being of less diameter than the larger end of a succeeding ring, each of said rings having an opening through it, means for inducing a draft through said casing and the openings in the rings, and a rotatable shaft upon which the muller wheels are mounted side by side.

6. In a grinding mill, the combination with a frame or casing, agitating means therein, a crushing device, said casing having a chamber in which the device operates and having an outlet from the chamber, an extension from one side of the casing having one end communicating with said opening and adapted to receive material delivered from the crushing chamber, a shaft passing through said extension, muller wheels arranged side by side on said shaft, each of said wheels having its periphery inclined from one side to the other, and a lining for said extension, said lining comprising a series of annular portions having inclined surfaces, one of said annular portions opposing each of said wheels and the inclination of said surfaces being substantially similar to the inclination of the wheels, and

along which surfaces the material is fed,

each of said wheels having its smaller end disposed proximate the larger end of a succeeding wheel, and the smaller end of one wheel being of less diameter than the contiguous end of an adjacent wheel, each of said wheels having an opening through it and the several openings forming a passage for the ground material, and means for inducing a draft through said casing and passage.

7. In a grinding mill, the combination with a frame or casing, agitating means therein, a crushing device, said casing having a chamber in which the device operates and having an outlet from the chamber, an extension from one side of the casing having one end communicating with said opening and adapted to receive material delivered from the crushing chamber, a shaft passing through said extension, muller wheels arranged side by side on said shaft, each of said wheels having its periphery inclined from one side to the other, a lining for said extension, said lining comprising a series of annular portions having inclined surfaces, one of said annular portions opposing each of said wheels and the inclination of said surfaces being substantially similar to the inclination of the wheels, and along which surfaces the material is fed, each of said wheels having its smaller end disposed proximate the larger end of a succeeding wheel, and the smaller end of one wheel being of less diameter than the contiguous end of an adjacent wheel, each of said wheels having an opening through it and the several openings forming a passage for the ground material, and means for inducing a draft through said casing and passage and means for endwise adjusting the lining relatively to the muller wheels.

8. In a grinding mill, the combination with a frame or casing, agitating means therein, a crushing roll, said casing having a chamber in which the roll operates and having an outlet from the chamber, an extension from one side of the casing having one end communicating with said opening and adapted to receive material delivered from the crushing chamber, a shaft passing through said extension, muller wheels arranged side by side on said shaft, each of said wheels having its periphery inclined from one side to the other, a lining for said extension, said lining comprising a series of annular portions having inclined surfaces, one of said annular portions opposing each of said wheels and the inclination of said surfaces being substantially similar to the inclination of the wheels, and along which surfaces the material is progressively fed, each of said wheels having its smaller end disposed proximate the larger end of a succeeding wheel, and the smaller end of one wheel being of less diameter than the contiguous end of an adjacent wheel, each of said wheels having an opening through it and the several openings forming a passage for the ground material, and means for inducing a draft through said casing and passage, a fan-case at the outer end of said extension having an opening communicating therewith, and a fan revolubly mounted in said casing and adapted to induce a suction through the extension to facilitate the feed of material from the crushing chamber and through said extension.

9. In a grinding mill, the combination with a frame having a crushing chamber and an opening therefrom, crushing means operable in said chamber, and means for feeding material from the chamber through said opening, a horizontal cylinder secured to the frame having one end connecting with said opening, said cylinder having an interior lining provided with step-like surfaces inclined to the axis of the cylinder and extending lengthwise of the cylinder, and muller wheels operable in the cylinder having peripheries inclined similarly to the inclination of the lining, the smaller end of one muller wheel being disposed proximate the larger end of a succeeding muller wheel, and the smaller end of one muller wheel being of less diameter than the larg 1' end of the succeeding muller wheel whereby the material ground by each muller is delivered within the interior of a succeeding muller, each of said mullers having an opening through it and the openings of the several mullers forming a common passageway for ground material.

10. In a grinding mill, the combination with a frame or casing having a crushing chamber, a crushing roll operable in said chamber, said frame or casing having side openings disposed substantially above and below the horizontal plane of the roll, a horizontal grinding cylinder connecting with said openings and forming a side extension of the frame or casing, open-center grinding mullers operable in the cylinder, means for discharging the material ground by one muller into the open center of a succeeding muller, a fan case connecting with the outer end of the cylinder, and a revoluble fan operating in said case, said crushing roll having wings, or vanes adapted to throw the crushed material upwardly during the crushing operation and said fan adapted to create a suction draft through the grinding cylinder and said upper opening to induce crushed material thrown up by the crushing roll to be drawn into the grinding cylinder, said roll having its vanes or wings adapted to feed another portion of the material into the grinding cylinder through the lower of said openings.

11. A grinding mill having in combination a casing; revoluble mullers arranged therein in succession, said mullers having substantially truncated form, and being open between the periphery and center to form a passage into which the material ground by the mullers passes; a crushing chamber communicating with one part of said casing; means for feeding material to said crushing chamber; crushing elements in said chamber, including means for imparting a tossing action to the crushed material; and means connecting with another portion of the chamber for inducing an air current through the mill whereby said current acts as a vehicle for carrying the material in suspension in the crushing chamber and the fine material delivered by respective mullers through the openings in the mullers to the discharge end of the casing.

12. In a grinding mill, the combination of a casing, and revoluble mullers arranged therein in succession, said mullers having a slanting ribbed surface, and said casing having on its interior corresponding slanting surfaces, each of said mullers having an opening through it, whereby the openings through the several mullers form a passage for the ground material, and means for inducing a draft through said casing and passage.

7 In testimony whereof I afliX my signature in presence of two witnesses.

JOHN A. lVELTON.

Vitnesses BERT J. ALLnsHoUsn, ED, G. SEIKEL.

Games of this patent may be obtained for five cents each, by addressing the Commissioner or retreats, Washington, D. C. 

